Energy efficient building solutions is a fast growing sector and new technology comes up every day. The standards varies from different areas, e.g. the german building standard can not be used to south italian building standards, because in Germany the standard has to fight cold temperatures, while in south Italy the standard has to fight warm temperatures. There are different solutions that may confuse the buyer, but all can be used in any region and here we shortly explain four of them:
Low Energy House is a building standard where design, material and technology is used to lower energy consumption and uses less energy from one or several sources. The standard varies but in Europe it refers to a house that uses half of the German or Swiss low-energy standards referred to below for space heating, normally in the range from 30 kWh/m²a to 20 kWh/m²a = 9,500 Btu/ft²/yr to 6,300 Btu/ft²/yr. Low-energy buildings typically use high levels of insulation, energy efficient windows, low levels of air infiltration and heat recovery ventilation to lower heating and cooling energy.
Passive House is a standard for energy efficient building, reducing ecological impact. It results in very low energy builiding that require little energy for space heating or cooling. This standard is not limited to only residental building, it is also well adapted in construction of public buildings, business facilities, schools, supermarkets to name few. The passive house standard is well developed in German speaking countries and Scandinavia. The Passive House standard is actually developed by a swedish and german collaboration.
The Passivhouse standard for central Europe requires that the building fulfills the following requirements:
- The building must be designed to have an annual heating demand as calculated with the Passivhaus Planning Package of not more than 15 kwh/m² per year = 4746 btu/ft² per year, in heating and 15 kwh/m² per year cooling energy OR to be designed with a peak heat load of 10W/m²
- Total energy source for electricity and etc., primary energy for heating, hot water and electricity must not be more than 120 kWh/m² per year = 3.79 × 104 btu/ft² per year.
- The building must not leak more air than 0.6 times the house volume per hour = n50 ≤ 0.6 / hour at 50 Pa (N/m²) as tested
A building based on the passive house concept in Darmstadt, Germany (photo: Wikipedia)
Zero Energy House is just what the name inteds, a building with zero net energy consumption and zero carbon emissions. Depending of country and technology the house use the electrical grid for energy storage but some are independent of grid. This standard offers several options for producing and conserving energy and many ways of measuring energy.
Example of Zero Energy House (Photo: zokazola.com – Stefan Behling)
Energy Plus House is the latest in energy efficient building (2013-09-28) and is a house that produces more energy from renewable energy sources than it consumes over an year. The house is a combination of microgeneration technology and low energy building technologies. This standard can be adapted to any kinds of construction as homes, offices, schools to name few…
Prototype of Zero Energy structure in Germany (photo: Wikipedia)
Numbers and some definition sources: Wikipedia